BENGALURU, Dec 4 (Reuters) - The European Space Agency postponed Wednesday's planned launch of its Proba-3 mission, aboard the Indian space agency's mainstay rocket, to observe the sun because of a technical issue and said it would now go ahead on Thursday.

The Proba-3, a two-satellite system developed over more than a decade and costing about 200 million euros ($210 million), is set to be launched from the Satish Dhawan Space Centre in India.

Using the Indian space agency's flagship Polar Satellite Launch Vehicle launch rocket, the mission is intended to advance global efforts to understand and mitigate the economic and technological risks of space weather.

"As part of standard operations in the preparation of the launch, a technical issue was detected ..." the ESA said on a post on X, without giving details.

Liftoff is now expected no earlier than 1042 GMT on Thursday.

The ESA has faced setbacks and delays in its launch programme, with the first commercial flight of the flagship Ariane 6 heavy launcher delayed to next year and access to Russia’s Soyuz rockets severed by a breakdown in relations over the war in Ukraine.

The Italian Vega C, which is used for small payloads, has been grounded for two years following a failed commercial debut, but is due to return to space later on Wednesday.

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(Reporting by Nivedita Bhattacharjee in Bengaluru, Editing by Timothy Heritage)

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